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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
    body{
        background-color: pink;
    }
@media only screen and(max-width: 500px){
    body {
        background-color:lightblue;
    }
}
}

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<body>
    <div>
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